1. Field of the Invention
The present invention relates to cycles and, more particularly, to quick-release and fastening assemblies for a cycle wheel to the fork of a bicycle frame.
The invention is particularly applicable to quick-release, and fastening, assemblies for fastening road bike and mountain bike wheels.
The invention also relates to a release/fastening assembly, including a skewer and a hub for such assembly, as well as a wheel and a cycle equipped with such a hub and assembly.
2. Background Information
Conventionally, a cycle wheel comprises a hub, a rim adapted to receive a tread and spokes or disks providing mechanical connection between the hub and the rim.
The hub comprises a hub body configured to be attached to the spokes or the discs and a hub shaft providing the mechanical connection of the hub to a front or rear fork of a bicycle frame.
The fork typically comprises two dropouts that are each attached to one of the ends of the shaft of the hub. The latter is therefore rotationally fixed when the rim rotates.
In the practice of sports cycling, one needs to be able to separate the wheel and the fork quickly and without tools in order, for example, to quickly assist a cyclist who has suffered a puncture with the repair, or simply for ease of transportation or storage of the bike.
A number of solutions have been proposed for quick release and fastening of the wheel to the fork.
These solutions are all based on the use of a skewer that extends through the shaft of the hub, with one end of the skewer projecting on each side of the hub. Each end of the skewer cooperating with one of the fork dropouts to enable the skewer to be fixed to the fork in the locked configuration and to enable the skewer to be removed from the fork in the unlocked configuration.
A first solution involves inserting each of the ends of the skewer into one the two bores carried by the dropouts. The patent documents EP 0810944 and U.S. Pat. No. 5,865,560 describe a solution of this type. Each bore of the dropouts has a passage slot for the bore to communicate with the outside and for inserting the skewer into the bore via movement through the passage slots. This movement is a mainly vertical movement when the cycle is in a rolling configuration.
A disadvantage of this type of solution is that, in the event of improper tightening of the skewer to the fork, the skewer may come out of the bores through the passage slots. The wheel may then separate from the frame when rolling, which may cause a fall with dramatic consequences.
To improve the safety of the cyclist, another solution provides for dropouts on the fork with bores that are closed, that is to say, devoid of passage slots. It is therefore necessary to insert the skewer through these bores along a direction corresponding to the axis of rotation of the wheel. One of the bores forms an internal thread into which a threaded end of the skewer is screwed. This solution, although satisfactory in terms of safety, has the disadvantage of requiring complete removal of the skewer from the hub during wheel replacement, which is time-consuming and tedious.
To overcome this disadvantage, another solution, such as that described in the patent document U.S. Pat. No. 6,089,675, provides a fork having a first dropout comprising a threaded bore without a passage slot and a second dropout comprising a non-threaded bore extended vertically by a passage slot. The hub/rod assembly may then be aligned with the two bores by passing the skewer through the passage slot of the second bore and then moving it along the axis of the skewer to engage the threaded end of the skewer with the threaded bore of the first dropout.
The aforementioned document describes a plurality of embodiments in which the skewer is pushed axially by a spring to pre-engage the threaded end of the skewer into the thread of the first bore.
The patent document US 2013/0270893 discloses an improvement over the aforementioned document by adding a skewer axial indexing system, which provides a stable open position for the skewer, despite the axial thrust of the return spring.
These solutions have the disadvantage of preventing or considerably complicating the extraction of the skewer from the hub. However, this extraction is necessary for the cleaning of these elements that are essential to the performance of the cycle or for replacing the wheel while keeping the same skewer.
These solutions also have a very specific hub design that makes them incompatible with commercially available skewers. Thus, a wheel of this type cannot be installed on a bike having a fork equipped with a standard skewer comprising two closed bores (devoid of passage slots). Such incompatibility drawback greatly limits the adoption of this concept by the end-user cyclist, the distribution network, and the hub manufacturer.
Furthermore, the handling of the skewer is complex.
In view of the foregoing, there is a need to provide a solution to overcome disadvantages mentioned above.
In particular, it would be very advantageous to have a robust, reliable, and economical solution that makes it possible to reduce, or even avoid, the risk of inadvertent detachment of the wheel while enabling easy dismounting thereof, easy extraction of the skewer out of the hub, and inter-compatibility of such a hub with already commercially available forks and rods.